Problem-Solving Exhaust Fan

Ventilate a bathroom without disturbing the room above

Ask This Old House Crew
Photo by Matt Kalinowski

We have a '40s-era house with a tiled tub/shower area inside an arched alcove. Unfortunately, the arch traps moisture and holds it against the plaster ceiling, which then mildews. I know ventilation would help, but there's a living space above the bathroom. Do you know any other way besides adding a fan to battle the mildew?
Craig, Elyria, OH


Tom Silva replies: Don't give up on the idea of a fan just yet. If a standard exhaust fan doesn't fit into your ceiling cavity, you can buy fans that mount remotely anywhere along the run of the duct. The ducting itself is typically 4 or 8 inches in diameter, small enough to fit between ceiling joists. (The smallest motors are about 10 inches in diameter.) Another advantage of the remote motor: It's less noisy than exhaust fans that have all the working parts right next to the intake grill.
If you can't install a fan of any type, however, you'll just have to wipe down the ceiling frequently. I'd scrape and clean the ceiling with a bleach solution to remove the mildew, then paint it with a high-quality high-gloss paint, which stands up well to repeated scrubbing. You can add a mildew preventative to the paint, too, for a longer fungi-free period, but mildew always comes back eventually. I suppose you could eliminate the arch, but it's a nice tile job, and I don't like to destroy something original that's done right.


TV Listings

Find TV Listing for This Old House and Ask This Old House in your area.